Plant & Animal Genomes XVI Conference

January 12-16, 2008
Town & Country Convention Center
San Diego, CA

Using Waxy Locus To Reveal Mutations In Rice Populations

Jaw-shu Hsieh¹ , Ming-chung Wu² , Yi-fang Chen¹ , Tze-fu Hsu² , Su-may Yu³ , Ming-hsing Lai⁴ , Chyr-guan Chern⁴ , Yue-ie C. Hsing²

¹  Department of Agronomy, National Taiwan University, Taipei, 106, Taiwan

²  Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 115, Taiwan

³  Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan

⁴  Taiwan Agricultural Research Institute, Wufeng, Taichung, 413, Taiwan

The Wx locus encodes a starch granule-bound ADP-glucose- glucosyl transferase, the Wx protein, which is responsible for amylose biosynthesis in the developing kernels and pollen grains. Because wx mutants are fully viable and the mutant phenotype can be easily scored in thousands of progeny, and the SNP rates in waxy locus are relatively high among rice varieties, we used this gene and agarose-TILLING to scan for mutations in several rice populations.
Two populations were used in the current studies. (1) About 100 rice land races were cultivated for thousands of years by the aboriginal people in Taiwan. The people belonged to 10 tribes and most of the rice races were javonica. Some of them were glutinous seeds. (2) TRIM, a T-DNA insertion mutant population. It was reported that the tagging efficiency is as low as 5% in T-DNA- or Tos17- induced populations. The mechanism of the somaclonal variation can be revealed by scanning for mutation in the population. We used 10 sets of primers which covered the whole waxy genes. We demonstrated that TILLING may quickly reveal the mutations in each land races and the results fitted well with amylopectin content. The SNP rates could be easily estimated in a huge numbers in the T-DNA mutant population by this method.